minicar: I get the mini part, but I don't understand how to beat the boss on level 2 when you are small. I tried jumping on him, but i either bounce off him or he kills me. What do I do!!!How do you defeat the boss once you are mini on super mario brothers on nintendo ds?oh no jumping on him will just bounce u back off, wat u need to do is the buttslam. its where u jump in the air and press down, mario will buttslam the boss. Do this 3 times and you just unlocked the secret world good luckHow do you defeat the boss once you are mini on super mario brothers on nintendo ds?I wall-kick off walls and land smack on the middle of his head.Since your small you have to ground pound him.Once your used to it you'll get.Doing that will bring you too World 4. P.S. When your on the file screen press L and then R and quickly select a file to play as Luigi.